Various liquids in bulk amounts are stored throughout the world in storage tanks. In particular, storage tanks are used extensively for the storage of liquid gasoline at retail gasoline stations. Necessarily, these stations are in populated areas and, therefore, there is always a danger associated with leaks from the tanks. Leaked gasoline poses a hazard to the environment as well as an obvious health hazard. The known problem is particularly troublesome in that gasoline storage tanks are usually buried underground and any leaks which develop are normally very slow initially. Underground storage tanks are susceptible to damage in those areas that are prone to earthquakes. Typical underground storage tanks are constructed of metal or fiberglass reinforced resinous material. Any earthquake is likely to cause a crack in the tank with a consequent leak. If the leak is slow, the same problems as above discussed exists. If the leak results in a large sudden loss, the problem is readily detected, but only after it is too late.
The problems associated with the present underground storage tanks are well known. Proposed local ordiances and federal regulations are in the drafting stage in an attempt to force the industry to safely store potentially dangerous liquids. Various solutions have been suggested to prevent leaked liquids or adequately contain leaked liquids. For example, some tank manufacturers have produced vaulted tank systems and have advertised them as effective secondary containment storage systems. In a vault system, the rigid storage tank is surrounded by another rigid tank or shell which acts as a containment vessel if the storage tank develops a leak. A slow leak in the storage tank is satisfactorily contained. The drawbacks associated with the vault systems now available include their cost, difficulty in installation due to their excessive weight, and lack of containment of the total system, including access openings and pipeline systems associated therewith.
There has now been discovered a liquid tank storage system which solves many of the problems inherent with the existing systems. The system of this invention is economical and provides total containment of the total system not available previously.